FIG. 3.

Coactivators potentiate the activities of the full-length AR and AF2 alone. (A) COS-1 cells were transfected as described in Materials and Methods. The coactivator was added at 200 ng per well, or various concentrations (20, 50, and 200 ng) of SRC1e were added. After transfection, cells were incubated with or without 10 nM mibolerone for 18 to 24 h before being harvested and assayed for CAT and β-galactosidase activities. Black bars show activity in the absence and gray bars show activity in the presence of hormone. The activity of AR in the absence of a coactivator and in the presence of mibolerone was set at 100%, and other values are expressed relative to this. The values above each of the gray bars show the fold induction of hormone-dependent activity relative to hormone-independent activity for each condition. (B) AR AF2 activity is potentiated by full-length SRC1 in yeast. Yeast (W3031B) was cotransfected with the AR LBD fused to a heterologous DBD, a lacZ reporter, and full-length SRC1a, SRC1e, or RIP140 and incubated overnight in the presence and absence of 100 nM mibolerone (MB). β-Galactosidase activity was measured and normalized for protein content. The experiment was repeated on several individual transformants. Results of a representative example are shown. NH, no hormone.